This invention is directed towards a counter which is designed to be placed in series or in parallel with a fluid supply line of a pulsed fluid system. The counter will monitor the number of cycles that fluid flows through the supply line in the pulsed fluid system. A pulse cycle in a pulsed fluid system begins when fluid starts to flow through the fluid supply line. The pulse cycle is completed when the fluid flow through the fluid supply line ceases.
Various devices utilize pressurized fluids to power or operate the particular device. When the device is a machine or apparatus which cycles, the number of times the apparatus cycles may need to be known. A typical example of a cycling apparatus which is powered by a pressurized fluid (normally compressed air) and has the requirement of cycle counting is a pneumatic pump for taking samples of groundwater or other liquids from a well or other monitoring site.
While the present invention is being described for exemplary purposes utilized with a groundwater sampling pump powered by compressed air, it is to be understood that the present invention can be utilized for counting cycles with any type of on/off fluid flow cycling device.
A groundwater sampling apparatus, preferably powered by compressed air, for use in conjunction with the present invention is disclosed in U.S. Pat. No. 4,489,779 issued Dec. 25, 1984 to Dickenson et al. and U.S. Pat. No. 4,585,060 issued Apr. 29, 1986 to Bernardin et al. both the disclosures of which are hereby incorporated by reference. The groundwater sampling apparatus disclosed in the above referenced patents is submerged beneath the water level of the groundwater in a well or monitoring site to a suitable depth for obtaining accurate and representative groundwater samples. The apparatus has a first chamber which is in communication with the groundwater and a second chamber which is in communication with a source of pressurized activating fluid (normally compressed air). The first and second chambers are separated by a flexible bladder member. The sample groundwater is conveyed through the apparatus by alternately pressurizing and venting or relieving the pressure in the second chamber which contracts and relaxes the bladder member. The contracting and relaxing of the bladder member will then alternately decrease and increase the volume of the first chamber. Sample groundwater is drawn into the first chamber during the increase in volume under the influence of natural hydrostatic head of the groundwater and is discharged through the pump outlet during the decrease in volume, thereby conveying the sample groundwater through the pump.
When taking samples of groundwater, it is first necessary to purge the water in the well or monitoring site in order to get a representative sample of the groundwater. The volume of groundwater in the well or monitoring site will normally be purged 3 to 5 times prior to taking a sample of the groundwater. Purging the volume of groundwater within the well 3 to 5 times requires a relatively large number of cycles of the pump. In order to be able to effectively and consistently retrieve acceptable groundwater samples, a person must accurately know the number of cycles the pump has gone through.
Accordingly, what is needed is an apparatus for counting the cycles of a fluidic activated device which is operated by a cyclical on and off flow of the operating fluid.